Chapter 10- Forces and motion Flashcards
What are the two types of forces
Contact and noncontact
What are the two kinds of contact forces
Impact forces, when surfaces Touch
strain forces, when a force builds up in the object on which a force is acting
Give an example of a strain force
The force inside of squashed Sponge ball. The Tensionis a strain force that builds up in A stretch elastic band
What is a noncontact force
Noncontact force that is exerted by one object on another without the objects touching.
Give an example of a noncontact force
Magnetic, electrostatic, gravitational forces
What is friction
Friction is a contact force that occurs between two surfaces when a push or pool could cause one service to move over the other
How is static friction created
Static friction, it’s a small pushing Or pulling force is generated to slide one surface over Another A frictional force of similar strength is generated between the surfaces in the opposite direction.
How do you increase the static friction
You can increase it by increasing the pushing or pulling force
What is static friction?
The force that exist between two surfaces when there is no movement
How is sliding friction created?
If the pushing or pulling force is further increased, one surface will slide over the other because the static friction cannot stop it.
What does the sliding Frictional force stop
The two surfaces from sliding
How do you reduce friction
A liquid applied to two surfaces feels the hollows and makes the contact between the surface is smoother
What do all surfaces have
Bumps and hollows
How do you increase friction?
If you press the surfaces it makes the projections and hollows lock together making a surface rougher also increases friction
What is air resistance?
What an object moves through the air, the object pushes on the air and the air pushes back with Force cold air resistance
How is air resistance increased
By the object moving through the air increasing in speed, the air pushes back in the greater the resistance pushing back on it
What is a steam line shape and when is it used
A shape with a pointed front, or a wedge shape, and curved body
It is used on Airplanes and cars
How does the Steamline shape work?
The shape is made to the air can flow over the Body easily, which reduces the air resistance
What is the mass of an Object?
The mass of an object is the amount of matter in it and is measured in grams or kilograms
What is the weight of an object
Weight of an object is the pool of the earths gravity on the object and is measured in newtons
How do you convert mass to newtons
1 kg of mess is almost ten newtons
What is a field
The region in which a noncontact force Acts
How do you calculate the gravitational field strength?
You divide the weight by mass.
What is the elastic limit
If the size of the mass is increased, the extension of the spring increases in proportion, up to a point called the elastic limit
What happens if you exceed the elastic limit
The spring will be permanently deformed and cannot return to its original length
What is a stop that is used in Laboratory investigations
The spring balance, it contains a spring in a device called a stop which prevents the spring from being stretched beyond It’s elastic limit
What is the spring used for
It can be used to measure and compare forces because it stretches in a regular way and forces are applied to it
What is the amount of stretch on
The amount of stretches measured on a scale which is calibrated into Newtons
When doing a graph on time and distance which unit should be on the X axis
Time in seconds the distance should be on the Y axis
What is the pressure and how do you calculate it
Wish I was a term used to describe the force acting over an area of no one size it’s equation is
Pressure=force
area
Do units for pressure are…
N/cm squared
N/m Squared
Ask nana about pressure exerted by a solid look in camera roll
Did I get help
Pressure at the bottom of the liquid is… Then that at the top of the liquid due to the…
The pressure the bottom of the liquid is higher than that at the top due to the weight of liquid above it
Ask Nanna❤️ for help by pressure exerted by gas
Look in your camera page 67
What is density and how do you work it out
The density of a substance is measured by the amount of matter that is present in a certain volume of it. It can be defined by this equation Density=mass over volume
What are the units for density
g/cm cubed
Kg/m cubed
How do you find the density of a solid
The density of a regular shaped solid such as a cube can be found easily. The mass is found by placing it on a top in balance. The volume is found by measuring the length of its sides and multiplying them together
There’s some ways to find the density of a regular shaped solid such as pebble
Finding the mess by putting it in a top pan balance
Filling a cylinder with water and then dropping the pebble inside and then measuring how much the water level increased
What are the instructions of determining the density of gas
1-The mass of the gas container and air found by placing it on the top pan balance. This is M
2-The air is sucked it was a vacuum pump, then is placed back on the balance to find its mass. This is M 2
3-The volume of the container is measured by opening the container under water. Water replaces the vacuum so that pouring the water out until measuring cylinder gives the volume, V.
4-The density is found by using the formula M2xm1 over v
What is the lever
Device that changes the direction In which a force Acts
A lever is composed Of two arms and a…
Fulcrum or pivot
The Fossett is applied to leave it to do its work is called the …
Effort
The force which resists the action of the effort is called the…
Load
What is the turning effect produced by a force around the fulcrum called?
The moment of the force
Study the picture in your camera roll of moments
How old do you know every part
How was the size of the moment found?
Multiplying the size of the force by the distance between the point at which the force acts and the fulcrum
What is the word equation for moment of force?
Moment of force=Force X distance from the fulcrum.
What is the moment measured in
Newton meters (N m)
Explain to me how to seesaw works
for the seesaw to balance and the two arms to be horizontal, the moment of the weight on one arm must be equal to the moment of the way on the other
Explain to me the law of the lever
When a body is in equilibrium, or balance, the sum of the clock was moments about any point, such as the fulcrum, equals the sum of the anti-clockwise moments about that point.
